Add a regression test for one of the crashes from https://bugs.swift.org/browse/SR-15792
Add a regression test for one of the crashes from https://bugs.swift.org/browse/SR-15792

rudkx/swift,glessard/swift,atrick/swift,benlangmuir/swift,ahoppen/swift,apple/swift,JGiola/swift,glessard/swift,apple/swift,rudkx/swift,rudkx/swift,benlangmuir/swift,benlangmuir/swift,gregomni/swift,gregomni/swift,rudkx/swift,ahoppen/swift,gregomni/swift,gregomni/swift,roambotics/swift,glessard/swift,apple/swift,roambotics/swift,atrick/swift,atrick/swift,roambotics/swift,apple/swift,benlangmuir/swift,ahoppen/swift,ahoppen/swift,apple/swift,ahoppen/swift,apple/swift,glessard/swift,roambotics/swift,JGiola/swift,benlangmuir/swift,atrick/swift,JGiola/swift,rudkx/swift,glessard/swift,benlangmuir/swift,roambotics/swift,atrick/swift,ahoppen/swift,atrick/swift,gregomni/swift,rudkx/swift,gregomni/swift,roambotics/swift,JGiola/swift,JGiola/swift,glessard/swift,JGiola/swift